December 6, 2021

I, Science

The science magazine of Imperial College

Who is Lise Meitner? And how did she revolutionise physical chemistry?

lise meitner imageYou may not have heard of Lise Meitner, but she was one of the most important scientists of the 20th century. In the first half of the 20th century physics experienced the revolutions of relativity and quantum theory, which culminated in a vastly greater understanding of the universe and some awe-inspiring advances in technology. Arguably the most awe-inspiring, and most terrifying, was the atomic bomb. Meitner played a major role in the understanding of the splitting of the atom (or ‘nuclear fission’), which is the process that occurs inside every nuclear warhead and inside every commercial nuclear power station on Earth.

Meitner was born in Vienna in 1878 and studied physics under Ludwig Boltzmann at the University there, receiving her doctorate in 1905 (she was only the second female ever to do so). She then left Vienna and moved to the University of Berlin, attending lectures by and assisting Max Planck until eventually working with the chemist Otto Hahn on radioactive isotopes. Her successes in Berlin included the discovery of a long-lived isotope of Protactinium with Hahn in 1917 and her own discovery of the ‘Auger’ effect – the process by which an electron near the core of an atom is ejected, allowing a higher energy electron to fall into the vacancy left behind and emit radiation – in 1922. The effect however is not named after Meitner but after the French physicist Pierre Victor Auger who independently discovered it later in 1923. In 1926 she became the first woman in Germany to be given a professorship.

Due to the rise of the Nazis (Meitner was born into a Jewish family, but had converted to Christianity in 1908) she had to leave Berlin in 1938 and fled to Stockholm. There she carried on her research but kept in contact with Hahn by mail, collaborating with him while he remained in Berlin.

The naming of the Auger effect would not be the last time Meitner’s work was overlooked. The Nobel Prize for Chemistry was awarded in 1944 solely to Hahn for his ‘discovery of the fission of heavy nuclei’ even though it is widely recognised that Meitner played a major role in the discovery. Her letters to Hahn from the time show that she guided Hahn through the design of the experiments and that she was key to understanding the results (along with another physicist, Otto Robert Frisch). Hahn did not include Meitner as co-author when he published the results on nuclear fission, maintaining that it would be dangerous to do so because of the war and that he would credit Meitner later. This never happened however and Hahn received sole credit, as well as the coveted Nobel.

Meitner was apparently content with this state of affairs as she wrote to a friend in November 1945 saying:

“Surely Hahn fully deserved the Nobel Prize for chemistry. There is really no doubt about it. But I believe that Otto Robert Frisch and I contributed something not insignificant to the clarification of the process of uranium fission – how it originates and that it produces so much energy and that was something very remote to Hahn.”

Although her work was never recognised by the Nobel committee she did receive the Enrico Fermi Award in 1966 with Hahn and Strassman, but for many (and this includes the author) this is too little to late for such an important contribution to science.

Meitner continued working in Sweden until 1960 when she moved to the UK to be closer to family. She died in Cambridge on 27th October 1968.

Lise Meitner was one of the most influential physicists (and considering what she worked on, one of the most influential human beings) of the 20th century. She contributed a large body of work and ideas to physics and was even called the “German Marie Curie” by Albert Einstein. To this day, she is barely known by the general public or indeed most scientists but the importance of her work deserves to be known by everyone.

Image: Wikimedia commons